PSA plays a variety of roles, the most familiar being screening to detect prostate cancer at an early stage. PSA also helps to define the Stages of Blue. Another role of PSA is to detect cancer relapse after surgery or radiation. Lastly, rises or declines in PSA after hormone therapy or chemotherapy help determine whether a treatment is working...

PSA is a powerful blood test for detecting a cancer relapse. However, there is always a danger of misinterpretation...